1. Field of the Invention
The present invention relates to a camera and a printer for producing a photographic print from a film exposed in the camera, and more particularly to a technique for determining an exposure amount at the time of printing.
2. Related Background Arts
Conventionally, in a photographic system employing the negative-positive method, an exposure for a negative photosensitive material (film) is determined on the side of camera, while an exposure for a positive photosensitive material (printing paper) is determined through an independent algorithm by light measurement of the negative film on the printer side in a laboratory. That is, these two exposure determinations are carried out separately and irrespectively from one another.
Specifically, there are disclosed photographic printing methods as follows; Japanese Laid-Open Patent Publication No. 2-278249, wherein strobe light emission data is recorded onto a film at the time of photographing and then, at the time of printing, the data is read out for classifying scenes so that exposure amount is computed by exposure calculation suitable for each scene; Japanese Laid-Open Patent Publication No. 3-41433, wherein object distance data is recorded onto a film at the time of photographing and then, at the time of printing, after performing light measurement at plural points in an image frame, and removing unnecessary measurement points in consideration of the above distance data, a printing exposure amount is obtained based on the measurement value; Japanese Laid-Open Patent Publication No. 3-51839 which describes a camera provided with means for recording data representing a position of main object in an image frame and a photographic printer which determines a printing exposure amount based on the data recorded on the film; Japanese Laid-Open Patent Publication No. 3-95542, wherein data on a distance measuring area including a main object is recorded onto a film at the time of photographing, and then, at the time of printing, a range of the main area is determined by reading the distance measuring area data and exposure is controlled based on the data within the range.
However, in the conventional cameras and printers, in spite of the camera exposing a main object with sufficiently high accuracy, light measurement is carried out on laboratory side before the printing operation, for determining an exposure amount at the time of printing. Accordingly, if the light measurement is imperfect, sometimes pictures which are under or over exposed are produced.